The present invention relates to protection of magnetic recording heads from electrostatic discharge (ESD), and more particularly to a microelectromechanical system (MEMS) for controllably shunting a recording head away from its driving circuit and/or electrical contacts during periods of non-operation.
Magnetic recording heads possess an acute sensitivity to damage or failure from ESD or electrical overstress (EOS) events, both during disc drive production and after assembly of the drive. During production, it is possible to electrically disconnect the recording head from the other electronic components of the drive, thereby offering protection against damage from ESD or EOS. Alternatively, systems have been proposed in which simple mechanical clamps are added to a disc drive during production to provide a shunt from reader elements of the recording head to each other or to ground to provide ESD protection. However, both of these systems tend to add expense to production of the drive, perhaps even greater than the benefit they provide, due to the addition of separate physical elements to the recording head and the requirement to enable and disable during different stages of production and use of the drive. Furthermore, such proposed systems are temporary and need to be removed or permanently disabled prior to final assembly.
Improvements are needed in the art of ESD protection for magnetic recording heads, which is the subject of the present invention.
The present invention is a magnetic recording head system that is protected against electrostatic discharge (ESD) and electrical overstress (EOS). The system includes a transducing read element and a drive circuit for connection to operate the transducing read element. A microelectromechanical switch has an input to receive an electrical control signal that selectively switches between a first state for protecting the transducing read element and a second state for operating the transducing read element.